Ripper depth limit based upon grade control depth

ABSTRACT

A control system for automatically controlling a ripper of a work vehicle based on a desired grade control depth. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth. A controller is in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to work vehicles, and more particularly to a system and method for automatically controlling a ripper of a work vehicle based on a desired grade control depth.

BACKGROUND OF THE DISCLOSURE

In order to break up soil and then move soil with a blade to achieve a desired grade, a ripper is commonly used. The ripper is commonly adjusted independently of a blade depth until the desired grade is achieved.

SUMMARY OF THE DISCLOSURE

In one embodiment, a control system for automatically controlling a ripper of a work vehicle based on a desired grade control depth is disclosed. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth. A controller is in communication with the at least one feedback device and is configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

In another embodiment, a work vehicle is disclosed. The work vehicle comprises a ripper and a control system. The control system automatically controls the ripper based on a desired grade control depth. The control system comprises at least one feedback device providing a feedback signal indicative of an actual grade control depth and a controller in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

In yet another embodiment, a method for automatically controlling a ripper of a work vehicle based on a desired grade control depth is disclosed. The method comprises providing a feedback signal indicative of an actual grade control depth. The method also comprises raising the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.

Other features and aspects will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a crawler according to one embodiment.

FIG. 2 is a perspective view of a motor grader according to another embodiment.

FIG. 3 is a schematic of a control system of a work vehicle according to yet another embodiment.

FIG. 4 is a schematic of a control system of a work vehicle according to another embodiment.

FIG. 5 is a schematic of an illustrative method for automatically controlling a ripper of a work vehicle based on a desired grade control depth.

Before any embodiments are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Further embodiments of the invention may include any combination of features from one or more dependent claims, and such features may be incorporated, collectively or separately, into any independent claim.

DETAILED DESCRIPTION

FIGS. 1 and 2 illustrate a work vehicle 10 having a blade 15, an operator station 20 having an operator interface 25, a ripper 30, and an engine 35. The work vehicle 10 may be any work vehicle to which a ripper may be coupled, such as a crawler or a motor grader, to name a few examples. The work vehicle 10 may be controlled by an operator located in the operator station 20. The operator may command the work vehicle 10 to move forward, move backward, and turn. In the case of the work vehicle 10, those commands are sent to hydraulic pumps, driven by the engine 35, which direct pressurized hydraulic fluid to hydraulic motors that turn tracks or wheels. The engine 35 may be a diesel engine. Alternatively, the tracks or wheels may be turned by electric motors.

The blade 15 is positioned at a front of the work vehicle 10 and may be attached to the work vehicle 10 in a number of different manners. In this embodiment, the blade 15 is attached to the work vehicle 10 through a linkage which includes a series of pinned joints, structural members, and hydraulic cylinders. This configuration allows the blade 15 to be moved up and down relative to the ground, rotate around a vertical axis (i.e., an axis normal to the ground), rotate around a longitudinal axis (e.g., a fore-aft axis of the work vehicle 10), and rotate around a lateral axis of the work vehicle 10 (i.e., a left-right axis of the work vehicle 10). These degrees of freedom permit the blade 15 to engage the ground at multiple depths and cutting angles. Alternative embodiments may involve blades with greater degrees of freedom, such as those found on some motor graders, and those with fewer degrees of freedom, such as “pushbeam” style blades found on some crawlers and blades which may only be raised, lowered, and rotated around a vertical axis as found on some excavators and skidders.

The operator may command movement of the blade 15 from the operator station 20. In the case of the work vehicle 10, those commands are sent, including mechanically, hydraulically, and/or electrically, to a hydraulic control valve. The hydraulic control valve receives pressurized hydraulic fluid from a hydraulic pump, and selectively sends such pressurized hydraulic fluid to a system of hydraulic cylinders based on the operator's commands. The hydraulic cylinders, which in this case are double-acting, in the system are extended or retracted by the pressurized fluid and thereby actuate the blade 15.

The ripper 30 is positioned at a rear of the work vehicle 10 and may be attached to the work vehicle 10 in a number of different manners. In this embodiment, the ripper 30 is attached to the work vehicle 10 through a linkage which includes a series of pinned joints, structural members, and hydraulic cylinders. This configuration allows the ripper 30 to be moved up and down relative to the ground.

With reference to FIG. 1, the illustrated work vehicle 10 is a crawler 40 for moving material. The crawler 40 includes a left track 45 and a right track 50. As used herein, “left” and “right” refer to the left and right sides of the operator when the operator is sitting within the operator station 20 and facing the blade 15. The ripper 30 is coupled to a rear of the crawler 40.

Referring to FIG. 2, the illustrated work vehicle 10 is a motor grader 55 for spreading and leveling dirt, gravel, or other materials. The motor grader 55 includes a plurality of left wheels 60 (right wheels not shown). The ripper 30 is coupled to a rear of the motor grader 55.

With reference to FIG. 3, the work vehicle 10 has a control system 65. The control system 65 automatically controls the ripper 30 of the work vehicle 10 based on a desired grade control depth 70. The operator may input the desired grade control depth 70 into the operator interface 25. The operator may also input a ripper depth limit 75 into the operator interface 25.

At least one feedback device 80 is provided. The feedback device 80 provides a feedback signal indicative of an actual grade control depth 85. The feedback device 80 may be a blade position sensor 90 coupled to the blade 15 for providing the feedback signal indicative of the actual grade control depth 85.

A controller 95 is in communication with the at least one feedback device 80 and the hydraulic cylinders to raise and lower the blade 15 as well as the hydraulic cylinders to raise and lower the ripper 30. The controller 95 is configured to raise the ripper 30 when the feedback signal indicates the actual grade control depth 85 is equal to the desired grade control depth 70. Alternatively, the controller 95 may be configured to raise the ripper 30 when the feedback signal indicates that the actual grade control depth 85 is approaching the desired grade control depth 70 or within some predetermined range such as plus or minus 1 inch. The controller 95 may also not allow the ripper 30 to lower below the ripper depth limit 75. Alternatively, the controller 95 may not allow the ripper 30 to approach a specified distance or range of the ripper depth limit 75, such as 1 inch or 1-6 inches.

Referring to FIG. 4, in another embodiment a grade control controller 100 is configured to control the blade 15 by communicating with the hydraulic cylinders for raising, lowering, and moving the blade 15. The at least one feedback device 80 is the blade position sensor 90 providing the feedback signal indicative of the actual grade control depth 85 to the grade control controller 100.

The controller 95 may be a ripper controller 105 that receives the feedback signal from the grade control controller 100 and is in communication with the hydraulic cylinders for raising and lowering the ripper 30. The ripper controller 105 is configured to raise the ripper 30 when the feedback signal indicates the actual grade control depth 85 is equal to the desired grade control depth 70. Alternatively, the ripper controller 105 may be configured to raise the ripper 30 when the feedback signal indicates that the actual grade control depth 85 is approaching the desired grade control depth 70 or within some predetermined range such as plus or minus 1 inch.

A speed sensor 110 may be provided. The speed sensor 110 may provide a speed feedback signal indicative of work vehicle speed 115 to the controller 95 (FIG. 3) or the grade control controller 100.

A track slip sensor 120 may be provided. The track slip sensor 120 may provide a track slip feedback signal indicative of track slip 125 relative to ground. The track slip sensor 120 is in communication with at least one of the controller 95 (FIG. 3), the grade control controller 100, and the ripper controller 105.

The grade control controller 100 is configured to lower the speed of the work vehicle 10 and/or raise the blade 15 when the track slip feedback signal indicates track slip 125 is occurring. The ripper controller 105 is configured to raise the ripper 30 when the track slip feedback signal indicates track slip 125 is occurring.

A ripper load feedback device 130 may be provided. The ripper load feedback device 130 may provide a ripper load feedback signal indicative of a ripper load 135. The ripper controller 105 receives the ripper load feedback signal and is configured to raise the ripper 30 when the ripper load feedback signal indicates the ripper load 135 has exceeded a threshold ripper load 140. Alternatively, the ripper controller 105 may raise the ripper 30 when the ripper load feedback signal indicates the ripper load 135 is approaching the threshold ripper load 140 or within some predetermined range of the threshold ripper load 140 such as 1 inch or 1-6 inches.

A method for automatically controlling a ripper 30 of a work vehicle 10 based on a desired grade control depth 70 is illustrated in FIG. 5. In Step 145, the feedback signal indicative of the actual grade control depth 85 is provided. In Step 150, the operator interface 25 where the operator can input the desired grade control depth 70 is provided. In Step 155, the ripper 30 is raised when the feedback signal indicates the actual grade control depth 85 is equal to the desired grade control depth 70.

Various features are set forth in the following claims. 

What is claimed is:
 1. A control system for automatically controlling a ripper of a work vehicle based on a desired grade control depth, the control system comprising: at least one feedback device providing a feedback signal indicative of an actual grade control depth; and a controller in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.
 2. The control system of claim 1, further comprising an operator interface where an operator can input the desired grade control depth.
 3. The control system of claim 1, further comprising an operator interface where an operator can input the desired grade control depth and a ripper depth limit where the controller will not allow the ripper to lower below the ripper depth limit.
 4. The control system of claim 1, wherein the work vehicle is at least one of a grader and a crawler.
 5. The control system of claim 1, further comprising a grade control controller configured to control a blade, the at least one feedback device is a blade position sensor providing the feedback signal indicative of the actual grade control depth to the grade control controller, the controller is a ripper controller that receives the feedback signal from the grade control controller and is configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.
 6. The control system of claim 5, further comprising a speed sensor providing a speed feedback signal indicative of work vehicle speed to the grade control controller and a track slip sensor providing a track slip feedback signal indicative of track slip relative to ground, the track slip sensor is in communication with the grade control controller and the ripper controller, where the grade control controller is configured to at least one of lower the speed of the work vehicle and raise the blade and the ripper controller is configured to raise the ripper when the track slip feedback signal indicates track slip is occurring.
 7. The control system of claim 6, further comprising a ripper load feedback device providing a ripper load feedback signal indicative of a ripper load where the ripper controller receives the ripper load feedback signal and is configured to raise the ripper when the ripper load feedback signal indicates the ripper load has exceeded a threshold ripper load.
 8. The control system of claim 7, further comprising an operator interface where an operator can input at least one of the desired grade control depth and the threshold ripper load.
 9. A work vehicle comprising: a ripper; and a control system for automatically controlling the ripper based on a desired grade control depth, the control system comprising: at least one feedback device providing a feedback signal indicative of an actual grade control depth; and a controller in communication with the at least one feedback device and configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.
 10. The work vehicle of claim 9, further comprising an operator interface where an operator can input the desired grade control depth.
 11. The work vehicle of claim 9, further comprising an operator interface where an operator can input the desired grade control depth and a ripper depth limit where the controller will not allow the ripper to lower below the ripper depth limit.
 12. The work vehicle of claim 9, further comprising a grade control controller configured to control a blade, the at least one feedback device is a blade position sensor providing the feedback signal indicative of the actual grade control depth to the grade control controller, the controller is a ripper controller that receives the feedback signal from the grade control controller and is configured to raise the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.
 13. The work vehicle of claim 12, further comprising a speed sensor providing a speed feedback signal indicative of work vehicle speed to the grade control controller and a track slip sensor providing a track slip feedback signal indicative of track slip relative to ground, the track slip sensor is in communication with the grade control controller and the ripper controller, where the grade control controller is configured to at least one of lower the speed of the work vehicle and raise the blade and the ripper controller is configured to raise the ripper when the track slip feedback signal indicates track slip is occurring.
 14. The work vehicle of claim 13, further comprising a ripper load feedback device providing a ripper load feedback signal indicative of a ripper load where the ripper controller receives the ripper load feedback signal and is configured to raise the ripper when the ripper load feedback signal indicates the ripper load has exceeded a threshold ripper load.
 15. The work vehicle of claim 14, further comprising an operator interface where an operator can input the desired grade control depth.
 16. A method for automatically controlling a ripper of a work vehicle based on a desired grade control depth, the method comprising: providing a feedback signal indicative of an actual grade control depth; and raising the ripper when the feedback signal indicates the actual grade control depth is equal to the desired grade control depth.
 17. The method of claim 16, further comprising providing an operator interface where an operator can input the desired grade control depth. 